Could somebody give me some css help please?

I’m an old school tables guy and could do with some help.

In the theme I am using the logo (on left) and navbar (on right) are laid out in such a way that the navbar will sit over the top of the logo and obscure it.

How can I change the CSS so that the nav bar moves below the logo. Logo still on left and nav bar on right, but logo higher on page than nav.

Current code:

<div id="body">
  <div id="wrapper">
    <div id="header">
      <div id="header-content">
        <div id="logo"> <a href="<?php echo get_option('home'); ?>" title="<?php bloginfo('name'); ?>" ><img src="<?php echo get_option('rascals_logo'); ?>" title="<?php bloginfo('name'); ?>" alt="logo" /></a> </div>
      </div>
      <div id="nav-container">
        <div id="nav-right" class="pngfix"></div>
        <div id="nav-left" class="pngfix">
         <ul id="nav">
         <?php include (TEMPLATEPATH . '/inc/page-exclusions.php'); ?>
    	</ul>
        </div>
        <!-- end menu-content -->
      </div>
      <!-- end menu-container -->
    </div>
    <!-- end header -->